'Arrow': Everything You Need to Know About the Big 'Constantine' Crossover

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Comic book nerds, we’re about to reach geek nirvana: John Constantine and Oliver Queen are finally coming face to face!

Fans of Constantine (R.I.P.) rejoiced when it was officially announced in August that the title character would be dusting off his trench coat and dropping by Arrow to help the team with an important matter of the mystical kind: restoring the soul of the newly resurrected Sara Lance.

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There’s reason to be excited: Matt Ryan, who led NBC’s shortlived series for 13 episodes, doesn’t miss a beat in this week’s episode, reprising his role as the beloved demon hunter.

“We’ve weaved in Matt very nicely and the Constantine character in very nicely,” Stephen Amell said recently on the set of Arrow, adding that Ryan is “fantastic on the show.” “I think that with keeping within the framework of our show, we lend ourselves to the things that make Constantine fun as a character.”

Constantine’s dry wit and quirky sense of humor, as well as his expertise in the unexplainable, is as evident as ever, and members of Team Arrow definitely take notice. (One of them even makes a joke about his unique personality.) In a memorable scene, the occult expert has Felicity Smoak deliver a peacock feather to him in the state-of-the-art lair, for no other reason than to use it scratch an itch in his back. 

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That’s all by design, giving fans of Arrow and Constantine supporters something to hang their hat on.

“We tried to stay true to the show,” executive producer Wendy Mericle told ETonline of bringing Constantine into the Arrow universe. “We wanted to honor his voice, who he was and how he was defined on the NBC show. Our writers – Brian Ford Sullivan and Oscar Balderrama – did a very good job capturing that voice.”

Fans of both characters will get to see just how these two DC heroes interact with each other early on in the episode, and it becomes evident that Oliver and Constantine’s history runs deep – very deep. Where and when Oliver first comes across the Brit should be familiar territory to Arrow fans who have been tuning in since season one.

But how does Constantine come into the fold? After discovering that the younger Lance sister is the stone-cold killer currently wreaking havoc on neighboring Star City towns, Oliver calls up his old pal to help him get her soul back before she was dipped in the magical hot tub (a.k.a. the Lazarus Pit).

When it came time to plant the seeds for Sara’s eventual return, due in part to the DC’s Legends of Tomorrow spinoff, Constantine was the most natural fit.

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“We had a situation where we knew Sara was going to come out of the Lazarus Pit and have these very big, significant issues to deal with,” Mericle said, “and Constantine seemed like the perfect person to bring her back and bring her soul back.”

Not surprisingly, this week’s episode, appropriately titled “Haunted,” is a big one for the Lance family. But, it’s a crucial argument between exes Laurel and Oliver in the hospital of Star City that greatly mirrors their defining hallway confrontation in season two, and may even trump it.

“It’s a very emotional story about a family getting a second chance to reunite with a loved one,” Mericle explained, “to explore the ramifications and the realities of what happens when you lose a sibling [or daughter].”

Even as Constantine becomes a more significant part of the story as it begins to unravel, it’s still Arrow through and through – though Mericle admitted that the hour is quite unusual in the context of the series.

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“It’s a departure, but definitely in keeping with season four in terms of Constantine and Matt Ryan bringing a sort of lightness and a little bit of banter to the show,” Mericle said, referencing the changes in Oliver’s demeanor this season. “With Oliver in a new place, happy and in love with Felicity, it just fit in with us exploring magic and mysticism through Damien Darhk and in the flashbacks. [John Constantine] fits that bill perfectly.”

“In that way it’s a departure but it’s very much in keeping with where we’re headed this season,” she added. (Speaking of Oliver and Felicity, they have a heartfelt conversation about loss and acknowledge the people they've lost over the years.) 

There are plenty of other non-Constantine nuggets to look forward to, such as the introduction of Oliver’s hip, new political strategist Alex Davis (Enlisted’s Parker Young), Diggle’s continued search for the truth behind the death of his brother and the mystery surrounding Ray Palmer.

When asked about the likelihood of a John Constantine return – things are left open-ended by episode’s end – Mericle closed the door on another reprisal, for now.

“That’s a good question,” she said. “We had him for this episode and it was important for this story. … For now, that was it. That was one episode we had him and it was great. We were excited to do it.”

Are you excited about this week’s Arrow-Constantine crossover? Don’t forget to come back here on Wednesday night following the East Coast airing to find out what’s coming up next for your favorite Star City crime-fighters!

airs Wednesdays at 8 p.m. ET/PT on The CW.